Differential expression of HLA-DR allospecificities on antigen specific T cell clones.

Serological and immunochemical analysis of T cell clones generated from an HLA-DR3, DR7 donor detected a lower expression of HLA-DR3 than of HLA-DR7 antigen. The defect in the expression of HLA-DR3 antigen appears to reflect abnormalities in regulatory mechanism(s), since the cell surface expression of this antigen could be increased by infecting T cell clones with human T lymphotropic virus I. This finding was paralleled by an increase in the level of mRNA encoded by the HLA-DR beta gene.